شکل برگها
شکل ظاهری برگها بسیار متنوع است. آنها به شکلهای دایره ٬بیضی ٬نیزه٬پر٬پنجه٬قلب و بسیاری شکلهای دیگر هستند، اما در مجموع میتوان آنها را به سه گروه تقسیم کرد: برگهای پهن، برگهای باریک و برگهای سوزنی. غیر از این سه گروه برخی گیاهان مانند سرو کوهی برگهای پولک مانند دارند. شگل برگ گیاهان یکی از راههای مهم شناسایی نوع گیاه است. طول بیشتر برگها میان ۵/۲ تا ۳۰ سانتیمتر است. اما برگ برخی از گیاهان بسیار بزرگ است، برای مثال طول بعضی از برگهای نوعی نخل آفریقایی به ۲۰ متر هم میرسد یا قطر نوعی از برگهای شناور که در مردابهای آمریکای جنوبی میرویند، به ۸/۱ متر میرسد، همچنین در مرداب انزلی، قطر برگهای دایرهای نیلوفر آبی گاه به بیش از ۵۰ سانتیمتر نیز میرسند. تعداد برگها در گیاهان گوناگون نیز متفاوت است. گیاهانی مانند گندم و ذرت دارای تنها چند برگ هستند. درختان کهنسال نارون صدها هزار برگ دارند. بعضی از گیاهان تنها یک برگ دارند. برگها یا ساده هستند یا مرکب. برگی که یک پهنک داشته باشد برگ مرکب است و پهنکهای برگ مرکب را برگچه مینامند. برگچههای برگ مرکب به صورت پر یا پنجه روی ساقه قرار میگیرند. در آرایش نوع پر، برگها شبیه شانهای در دو طرف رگبرگ اصلی جای میگیرند، مانند برگ درخت گردو و زبان گنجشک. برگچههای برگهای مرکب پنجهای از انتهای دمبرگ میرویند، مانند برگ شبدر. در برخی از گیاهان، برگچهها به برگچههای کوچکتری تقسیم میشوند و این برگها را برگ مرکب دوگانه مینامند مانند برگ هویج و شبت (شوید). لبه و طرح رگبرگهای پهنک برگها گوناگون است. بعضی پهنک برگها دارای لبه صاف، بعضی دانهدار و بعضی کنگرهدار هستند. لبه بیشتر برگهای باریک و سوزنی صاف است. لبه پهنک بیشتر گیاهانی که در منطقه اقلیمی استوایی و نیمه استوایی میرویند نیز صاف است. لبه پهنک درختانی مانند، پرتقال، نارون و گیلاس دانهدار است و همچنین روی آنها روزنههایی نیز وجود دارد که بخشی از آب اضافی گیاه از راه این روزنهها خارج میشود. لبه برگ برخی از گیاهان، مانند توت سفید و بلوط جنگلی، کنگرهدار است.
شکلهای برگها
[ویرایش]در دانش گیاهشناسی برگها به شکلهای زیر دستهبندی میشوند (لاتین، به همراه توضیح انگلیسی و ترجمه پارسی آن):
- Acicular (acicularis): Slender and pointed, needle-like (سوزنیشکل)
- Acuminate (acuminata): Tapering to a long point (هرمیشکل)
- Acute: pointed, having a short sharp apex angled less than ۹۰° (دارای زاویهٔ تند کمتر از ۹۰ درجه)
- Aristate (aristata): Ending in a stiff, bristle-like point (دارای انتهای زبر و محکم)
- Asymmetrical: With the blade shape different on each side of the midrib (با اجزاء گوناگون تیغیشکل)
- Basal: arising from the crown, bulb, rhizome or corm, etc. as opposed to cauline (تاجیشکل، چراغیشکل)
- Bipinnate (bipinnata): Each leaflet also pinnate (پرمانند)
- Caudate: tailed at the apex (دمدار)
- Cauline: borne on the stem as opposed to basal (موازی با ساقه)
- Compound: Not simple; the leaf is broken up into separate leaflets, and the leaf blade is not continuous (دارای برگچه)
- Cordate (cordata): Heart-shaped, with the petiole or stem attached to the cleft (قلبمانند)
- Cuneate (cuneata): Triangular, stem attaches to point (مثلثی، وصلشده توسط سطح برگ)
- Deltoid (deltoidea) or deltate: Triangular, stem attaches to side (مثلثی، توسط کنارههای برگ)
- Digitate (digitata): Divided into finger-like lobes (انگشتدار)
- Elliptic (elliptica): Oval, with a short or no point (بیضیشکل)
- Entire: having a smooth margin without notches or indentations (دارای یک لبه صاف و بدون شکاف و دندانه)
- Falcate (falcata): Sickle-shaped (داسیشکل)
- Fenestrate (fenestrata) "windowed" with holes (e.g. Monstera deliciosa or Aponogeton fenestralis), or window-like patches of translucent tissue. (cf Perforate) (پنجرهمانند)
- Filiform (filiformis): Thread- or filament-shaped (رشتهایشکل)
- Flabellate (flabellata): Semi-circular, or fan-like (نیمدایرهای یا بادبزنمانند)
- Hastate, spear-shaped (hastata): Pointed, with barbs, shaped like a spear point, with flaring pointed lobes at the base (نیزهمانند)
- Laciniate: Very deeply lobed, the lobes being very drawn out, often making the leaf look somewhat like a branch or a pitchfork (چنگالمانند)
- Laminar: Flat (like most leaves) (صاف، مانند اکثر برگها)
- Lance-shaped, lanceolate (lanceolata): Long, wider in the middle (دراز و دارای میانهای پهن)
- Linear (linearis): Long and very narrow (دراز و باریک)
- Lobed (lobata): With several points (دارای چندین نوک)
- Mucronate: Ending abruptly in a sharp point (دارای انتهایی تیز)
- Obcordate (obcordata): Heart-shaped, stem attaches to tapering point (قلبمانند)
- Oblanceolate (oblanceolata): Top wider than bottom (انتهای فوقانی عریض تر از انتهای تحتانی)
- Oblong (oblongus): Having an elongated form with slightly parallel sides (کشیده و قرینه)
- Obovate (obovata): Teardrop-shaped, stem attaches to tapering point (اشکیشکل)
- Obtuse (obtusus): With a blunt tip (دارای لبهٔ بینوک)
- Orbicular (orbicularis): Circular (دایرهای)
- Ovate (ovata): Oval, egg-shaped, with a tapering point (تخممرغیشکل)
- Palmate (palmata): Consisting of leaflets or lobes radiating from the base of the leaf. (پنجهای)
- Pedate (pedata): Palmate, with cleft lobes (نخلیشکل)
- Peltate (peltata): Rounded, stem underneath (دوار)
- Perfoliate (perfoliata): Stem through the leaves (ساقه از میان برگ ردشده)
- Perforate (perforata): marked with patches of translucent tissue, as in Crassula perforata and Hypericum perforatum, or perforated with holes (cf "Fenestrate") (مشخصشده با تکههای بافت شفاف)
- Pinnate (pinnata): Two rows of leaflets (شانهای)
- Odd-pinnate, imparipinnate: Pinnate with a terminal leaflet (شانهای فرد یا شانهای بسته)
- Paripinnate, even-pinnate: Pinnate lacking a terminal leaflet (شانهای زوج یا شانهای باز)
- Pinnatifid and pinnatipartite: Leaves with pinnate lobes that are not discrete, remaining sufficiently connected to each other that they are not separate leaflets. (دارای برگچههای پیوسته و پرمانند)
- Bipinnate, twice-pinnate: The leaflets are themselves pinnately-compound (دوشانهای یا شانهای مضاعف)
- Tripinnate, thrice-pinnate: The leaflets are themselves bipinnate (سهشانهای)
- Tetrapinnate: The leaflets are themselves tripinnate. (چهارشانهای)
- Pinnatisect (pinnatifida): Cut, but not to the midrib (it would be pinnate then) (برشخورده)
- Serenoa repens showing pleated elliptic leaves of seedling and pleated palmate leaves of mature plant (بیضویشکل)
- Plicate (plicatus, plicata): folded into pleats, usually lengthwise, serving the function of stiffening a large leaf. (تاشده به شکل بیضی)
- Pungent: Having hard, sharp points. (دارای انتهای تیز و زبر)
- Reniform (reniformis): Kidney-shaped (کلیهمانند)
- Retuse: With a shallow notch in a broad apex (با یک شکاف کمعمق در انتهای فوقانی عریضش)
- Rhomboid (rhomboidalis): Diamond-shaped (الماسمانند)
- Round (rotundifolia): Circular (گرد یا دایرهمانند)
- Sagittate (sagittata): Arrowhead-shaped (تیرکمانی)
- Simple: Leaf blade in one continuous section, not divided into leaflets (not compound) (به شکل یک تیغ کلی)
- Spear-shaped (نیزهمانند)
- Spatulate, spathulate (spathulata): Spoon-shaped (قاشقمانند)
- Subulate (subulata): Awl-shaped with a tapering point (درفشمانند)
- Subobtuse (subobtusa): Somewhat blunted, neither blunt nor sharp (نیمهتیز)
- Sword-shaped (ensiformis): Long, thin, pointed (دراز، باریک و ریز)
- Trifoliate (or trifoliolate), ternate (trifoliata): Divided into three leaflets (سهبرگچهای)
- Tripinnate (tripinnata): Pinnately compound in which each leaflet is itself bipinnate (سهشانهای)
- Truncate (truncata): With a squared off end (با انتهای مربعیشکل)
- Unifoliate (unifoliata): With a single leaf (تکبرگی)
Image | Term | Latin | Refers principally to | Description |
---|---|---|---|---|
acicular | acicularis | whole leaf | Slender and pointed, needle-like | |
acuminate | acuminatus | leaf tip | Tapering to a long point in a concave manner | |
acute | leaf tip or base | Pointed, having a short sharp apex angled less than 90° | ||
apiculate | apiculatus | leaf tip | Tapering and ending in a short, slender point | |
aristate | aristatus | leaf tip | Ending in a stiff, bristle-like point | |
asymmetrical | whole leaf | With the blade shape different on each side of the midrib | ||
attenuate | attenuatus | leaf base | Having leaf tissue taper down the petiole to a narrow base and always having some leaf material on each side of the petiole | |
auriculate | auriculatus | leaf base | Having ear-shaped appendages reaching beyond the attachment to the petiole or stem (in case of a seated leaf) | |
caudate | caudatus | leaf tip | Tailed at the apex | |
cirrus, cirrate | leaf tip | Having a rachis that extends beyond the leaf blade or leaflets into a long whip-like extension or cirrus (common in climbing palms); antonym: ecirrate | ||
cordate, cordiform | cordatus | whole leaf or base | Heart-shaped, with the petiole or stem attached to the notch | |
cuneate | cuneatus | leaf base | Triangular, wedge-shaped, stem attaches to point | |
cuneiform | whole leaf | Narrowly triangular, widest on the opposite end from the stem, with the corners at that end rounded | ||
cuspidate | cuspidatus | leaf tip | With a sharp, elongated, rigid tip; tipped with a cusp | |
deltoid, deltate | deltoideus | whole leaf | Shaped like the Greek letter delta; triangular with stem attached to side | |
digitate | digitatus | whole leaf | A palmately compound leaf with leaflets, similar to palmate[۱] | |
ecirrate | leaf tip | Without a cirrus; antonym: cirrate | ||
elliptic | ellipticus | whole leaf | Shaped like an ellipse (widest at mid-blade and with similar convex tapering towards apex and base), with a short or no point | |
emarginate | emarginatus | leaf tip | Slightly indented at the tip | |
ensiform | ensiformis | whole leaf | Shaped like a sword; long and narrow with a sharp pointed tip | |
falcate | falcatus | whole leaf | Sickle-shaped | |
fenestrate | fenestratus | leaf surface features | Large openings through the leaf; see perforate; sometimes used to describe leaf epidermal windows | |
filiform | filiformis | whole leaf | Thread- or filament-shaped | |
flabellate | flabellatus | whole leaf | Semi-circular or fan-like | |
hastate | hastatus | whole leaf or base | Spear-shaped: pointed, with barbs, shaped like a spear point, with flaring pointed lobes at the base | |
laciniate | lacinatus | whole leaf | Very deeply lobed with the lobes being very drawn out and often making the leaf look somewhat like a branch or a pitchfork | |
laminar | 3-D shape | Flat (like most leaves) | ||
lanceolate | lanceolatus | whole leaf | Long, wider in the middle, shaped like a lance tip | |
linear | linearis | whole leaf | Long and very narrow like a blade of grass | |
lobed | lobatus | whole leaf | Being divided by clefts; may be pinnately lobed or palmately lobed | |
lorate | loratus | whole leaf | Having the form of a thong or strap | |
lyrate | lyratus | whole leaf | Shaped like a lyre, pinnately lobed leaf with an enlarged terminal lobe and smaller lateral lobes. See also List of lyrate plants. | |
mucronate | mucronatus | leaf tip | Ending abruptly in a small sharp point as a continuation of the midrib[۲] | |
multifid | multi + findere | whole leaf | Cleft into many parts or lobes | |
obcordate | obcordatus | whole leaf | Heart-shaped, stem attaches at the tapering end | |
oblanceolate | oblanceolatus | whole leaf | Much longer than wide and with the widest portion near the tip; reversed lanceolate | |
oblique | leaf base | Asymmetrical leaf base, with one side lower than the other | ||
oblong | oblongus | whole leaf | Having an elongated form with slightly parallel sides; roughly rectangular | |
obovate | obovatus | whole leaf | Teardrop-shaped, stem attaches to the tapering end; reversed ovate | |
obtrullate | whole leaf | Reversed trullate; the longer sides meet at the base rather than the apex. | ||
obtuse | obtusus | leaf tip or base | Blunt, forming an angle > 90° | |
orbicular | orbicularis | whole leaf | Circular | |
ovate | ovatus | whole leaf | Egg-shaped, with a tapering point and the widest portion near the petiole | |
palmate | palmatus | whole leaf | Palm-shaped, i.e. with lobes or leaflets stemming from the leaf base[۳] | |
palmately lobed | palmatus | whole leaf | Lobes spread radially from a point[۴] | |
palmatifid | palma + findere | whole leaf | Palm-shaped, having lobes with incisions that extend less than halfway toward the petiole | |
palmatipartite | palma + partiri | whole leaf | Having palmate lobes with incisions that extend over halfway toward the petiole | |
palmatisect | palma + secare | whole leaf | Having palmate lobes with incisions that extend almost up, but not quite to the petiole. | |
pandurate | panduratus | whole leaf | Fiddle-shaped; obovate with a constriction near the middle. | |
pedate | pedatus | whole leaf | Palmate, with cleft lobes[۵] | |
سپروار | peltatus | stem attachment | A round leaf where the petiole attaches near the center, e.g. a lotus leaf | |
perfoliate | perfoliatus | stem attachment | With the leaf blade surrounding the stem such that the stem appears to pass through the leaf | |
perforate | perforatus | leaf surface features | Many holes, or perforations, on leaf surface. Compare with fenestrate. | |
pinnately lobed | pinna + lobus | whole leaf | Having lobes pinnately arranged on the central axis | |
pinnatifid | pinna + findere | whole leaf | Having lobes with incisions that extend less than halfway to the midrib | |
pinnatipartite | pinnatus + partiri | whole leaf | Having lobes with incisions that extend more than halfway to the midrib | |
pinnatisect | pinnatus + sectus | whole leaf | Having lobes with incisions that extend almost to, or up to, the midrib | |
plicate | plicatus | 3-D shape | Folded into pleats, usually lengthwise, serving the function of stiffening a large leaf | |
reniform | reniformis | whole leaf | Shaped like a kidney, with an inward curve on one side | |
retuse | leaf tip | With a shallow notch in a round apex | ||
rhomboid, rhombic | rhomboidalis | whole leaf | Diamond-shaped | |
rounded | rotundifolius | leaf tip or base | Circular, no distinct point | |
semiterete | 3-D shape | Rounded on one side and flat on the other | ||
sinuate | sinuatus | 3-D shape | Circularly-lobed leaves | |
sagittate | sagittatus | whole leaf | Arrowhead-shaped with the lower lobes folded, or curled downward | |
spatulate | spathulatus | whole leaf | Spoon-shaped; having a broad flat end which tapers to the base | |
spear-shaped | hastatus | whole leaf | See hastate. | |
subobtuse | subobtusus | leaf tip or base | Somewhat blunted; neither blunt nor sharp | |
subulate | subulatus | leaf tip | Awl-shaped with a tapering point | |
terete | 3-D shape | Cylindrical with a circular or distorted circular cross-section and a single surface wrapping around it with no grooves or ridges. Subterete means the leaves are not completely terete, as seen in various lichens and succulents. | ||
trullate | whole leaf | Shaped like a masonry trowel | ||
truncate | truncatus | leaf tip or base | With a squared-off end | |
undulate | undulatus | 3-D shape | Wave-like | |
unifoliate | unifoliatus | compound leaves | With a single leaflet; it is distinct from a simple leaf by the presence of two abscission layers and often by petiolules and stipels. |
نگارخانه
[ویرایش]-
جدول ریختشناسی برگها
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برگهای پر مانند (به انگلیسی: Oddly pinnate)
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برگهایی که کاملاً ساقه را دوره کردهاند (به انگلیسی: Perfoliate)
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برگهای سادهٔ نخلی شکل
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برگ دندانه دار گیاه (به انگلیسی:Adenanthos sericeus)
جستارهای وابسته
[ویرایش]منابع
[ویرایش]- مشارکتکنندگان ویکیپدیا. «Glossary of leaf morphology». در دانشنامهٔ ویکیپدیای انگلیسی، بازبینیشده در ۱۹ فوریه ۲۰۱۷.
- ↑ Index of Garden Plants, Mark Griffiths, Timber Press, 1992
- ↑ Mucronate بایگانیشده در ۲۰۱۶-۰۳-۰۳ توسط Wayback Machine, Answers.com, from Roget's Thesaurus.
- ↑ "palmate (adj. palmately)". GardenWeb Glossary of Botanical Terms. iVillage GardenWeb. 2006. Archived from the original on 13 February 2009. Retrieved 19 October 2008.
- ↑ Nelson, Randal C. (2009) [2012]. "Leaf description glossary". University of Rochester. Archived from the original on 1 August 2020. Retrieved 2 November 2017.
- ↑ "Pedate leaf". Retrieved 24 February 2014.